Depletion of non-renewable fuels, emissions beyond the atmospheric carrying capacity, and total amount of energy, used create a variety of sustainable scale problems.

"Our principle constraints at present are neither lack of energy and material resources, nor of essential physical and biological knowledge... During the last two centuries we have evolved...a culture so heavily dependent upon the continuance of exponential growth for its stability that it is incapable of reckoning with problems of nongrowth."